A technique which generates a thumbnail image as a representative still image for each of data concerning a still image, motion image, and voice, and manages these thumbnail images in relation to the still image, motion image, and voice is conventionally proposed.
For example, Japanese Patent Laid-Open No. 2003-348530 proposes an apparatus which relates data concerning a still image to data concerning voice.
Also, Japanese Patent Laid-Open No. 2003-111011 proposes a motion image searching apparatus capable of generating a useful representative still image without generating any meaningless frame as a representative still image, as an apparatus for generating a thumbnail image as a better representative still image.
Furthermore, Japanese Patent Laid-Open No. 2001-298711 proposes an apparatus which extracts voice data for a thumbnail image without editing or processing the data.
A basic voice signal processing method is described in Sadahiro Furui, “Digital Voice Processing”.
Also, an example of a method of converting the speech rate of a voice signal is described in Masao Kasuga, Tetsuo Funada, Shinji Hayashi, and Kazuya Takeda, “Voice Information Processing”.
It is possible by any of the above techniques to manage related data concerning a still image, motion image, and voice by grouping the data, and read out the related data as a data group.
It is also possible to generate a thumbnail image as a more appropriate representative image for related data, and allow a user to recognize the relation of the data group within a short time by looking the thumbnail image.
Unfortunately, although a more appropriate thumbnail image can be generated, no apparatus which generates thumbnail voice as more appropriate representative voice has been proposed.